ANEMIA, PERNICIOUS

General Information

DEFINITION--Anemia caused by inadequate absorption of vitamin B-12. Vitamin B-12 is found only in food of animal origin, such as meat, fish and dairy products. The symptoms of pernicious anemia develop slowly and subtly and may not be recognized right away.

BODY PARTS INVOLVED--Blood, which affects all body cells; stomach.

SEX OR AGE MOST AFFECTED--Adults between ages 50 and 60. This is uncommon in children.

SIGNS & SYMPTOMS

• Weakness, especially in the arms and legs.
• Sore tongue.
• Nausea, appetite loss and weight loss.
• Bleeding gums.
• Numbness and tingling in the hands and feet.
• Difficulty maintaining proper balance.
• Pale lips, tongue and gums.
• Yellow eyes and skin.
• Shortness of breath.
• Depression.
• Confusion and dementia.
• Headache.
• Poor memory.

CAUSES

• Absence of intrinsic factor, a chemical secreted by the stomach's membrane lining that makes absorption of vitamin B-12 possible. The reason for the absence of intrinsic factor is unknown, but it may be a genetic deficiency or autoimmune disorder.
• Decreased production of hydrochloric acid, especially following stomach surgery or in combination with the absence of intrinsic factor. Hydrochloric acid is also necessary for absorption of vitamin B-12.

RISK INCREASES WITH

• Improper diet, especially a vegetarian diet lacking vitamin B-12 and without supplements.
• Thyroid disease.
• Diabetes mellitus.
• Previous stomach surgery, stomach cancer or gastritis.
• Bulimia or anorexia nervosa.
• Family history of pernicious anemia.
• Genetic factors. The disorder is most common in people of Northern European ancestry. It is rare in blacks and Asians.

HOW TO PREVENT--If you have had stomach surgery or gastritis, have regular vitamin B-12 injections. See Medication.

What To Expect

DIAGNOSTIC MEASURES--

• Your own observation of symptoms.
• Medical history and physical exam by a doctor.
• Laboratory blood studies.
• Radioactive studies, such as the Schilling test using radioactive vitamin B-12.
• Bone marrow test.

APPROPRIATE HEALTH CARE

• Self-care after diagnosis.
• Doctor's treatment.

POSSIBLE COMPLICATIONS

• Congestive heart failure.
• Double vision.
• Greater susceptibility to infections.
• Impotence in males.

PROBABLE OUTCOME--This condition is currently considered incurable. However, regular vitamin B-12 injections will control symptoms indefinitely and reverse complications. Some symptoms should start to disappear within a few days after treatment begins; others may take several months.

How To Treat

GENERAL MEASURES----Avoid very hot water and heating pads. Your nervous system may not be able to detect dangerously high temperatures.

MEDICATION--

• Your doctor will prescribe vitamin B-12 injections. The amount depends on the extent of your illness. The usual dosage is 1 injection a day for 7 days, then 1 injection a week for 1 month, then once a month for the rest of your life.
• Learn to give yourself vitamin B-12 injections, because oral supplements are inadequate. Lifetime treatment is essential. Even with treatment, your ability to absorb vitamin B-12 will not be normal.

ACTIVITY--Physical activity may need to be restricted until symptoms of weakness and balance problems disappear.

DIET--

• No special diet. Raw meat and raw liver are no longer prescribed.
• Iron supplements may be necessary.

Call Your Doctor If

• You have symptoms of pernicious anemia.
• Symptoms don't improve in 2 weeks, despite treatment.